Change redirect deletion date

doc/operations/incident_management/alert_notifications.md

@@ -4,5 +4,5 @@ redirect_to: 'paging.md'
 
 This document was moved to [another location](paging.md).
 
-<!-- This redirect file can be deleted after <2022-01-21>. -->
+<!-- This redirect file can be deleted after 2021-04-21 -->
 <!-- Before deletion, see: https://docs.gitlab.com/ee/development/documentation/#move-or-rename-a-page -->